diff -ur a/include/gemmi/json.hpp b/include/gemmi/json.hpp
--- a/include/gemmi/json.hpp
+++ b/include/gemmi/json.hpp
@@ -38,6 +38,7 @@
 
 inline std::string as_cif_value(const sajson::value& val) {
   switch (val.get_type()) {
+    case sajson::TYPE_INTEGER:
     case sajson::TYPE_DOUBLE:
       return val.as_string();
     case sajson::TYPE_NULL:
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<div class='path'>path: <a href='/guix/log/?id=b380fbca8859f7ba0f41703a970ddd26b4590eb4'>root</a>/<a href='/guix/log/etc?id=b380fbca8859f7ba0f41703a970ddd26b4590eb4'>etc</a>/<a href='/guix/log/etc/gnu-store.mount.in?id=b380fbca8859f7ba0f41703a970ddd26b4590eb4'>gnu-store.mount.in</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/etc/gnu-store.mount.in?id=b380fbca8859f7ba0f41703a970ddd26b4590eb4&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2020-05-17 15:16:52 +0200'>2020-05-17</span></td><td><a href='/guix/commit/etc/gnu-store.mount.in?id=301572aa87a9587465277d48325dd88fcbf1b312'>etc: Add a systemd unit to bind-mount @storedir@ read-only.</a><span class='msg-avail'>...<span class='msg-tooltip'>* etc/gnu-store.mount.in: New file.
* nix/local.mk (nodist_systemdservice_DATA): Add it.
(etc/%.mount): New rule for it.
* etc/guix-install.sh (sys_enable_guix_daemon): Install it.
* doc/guix.texi (Binary Installation): Document it.
* .gitignore: Ignore changes to it.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>